Use of the chlorate candle as a source of oxygen for the emergency destruction of classified material

ABSTRACT

A system for emergency destruction of classified materials stored in a security container. A chlorate candle is remotely situated from the material and utilized as an oxygen source for destruction of the material by burning. An optional compressed air source is attached to the system to be activated at the completion of the oxygen burn to further ensure complete destruction of the material.

United States Patent 1191 111.1 3,871,281 Leonard et al. 1 Mar. 18, 1975 [54] USE OF THE CHLORATE CANDLE AS A 3,573,001 3/1971 Bmard 23/281 SOURCE OF OXYGEN FOR THE 3,643,229 2/1972 Muywuld et a1. .1 109/29 EMERGENCY DESTRUCTION OF 3,650,..-6 3/197- Conroy et z1|...... 109/25 3,730,111 5/1973 Matthews 109/24 X I CLASSIFIED MATERIAL 3,736,104 5/1973 Churchill et a1. 23/281 75 Inventors: Joseph T. Leonard, Falls Church; 3,797,412 3/1974 DiPaola et al. 109/24 X Donald E. Field, Springfield, both of Va. Primary Examiner-Dennis L. Taylor {73] Assignee: The United States of A i as Attorney, Agent, 0r'Firm-R. S. Sciascia; Arthur L.

represented by the Secretary of th g; NOrmfln BTOWH Navy, Washington, DC

' A 1 7 [22] Flled ug 24, 9 3 ABSTRACT [21] Appl. No.: 391,408 I 1 A syis tem f0; emergency destruction oi clglssified mav term 5 store 1n a securlty container. 6 orate can- [52] :J.S.((:Il. .ibslog/gg dle is remotely Situated from the material and utilized gz' as an oxygen source for destruction of the material by burning. An optional compressed air source is atlO9/26 23/281 110/18 R tached to the system to be activated at the completion {56] Re erenc Cite of the oxyfgeln burn tolfurther' ensure complete de struction o t e material UNITED STATES PATENTS 3,542,522 l1/I970. Mausteller 23/281 2 Claims, 1 Drawing Figure BACKGROUND OF THE INVENTION The invention relates to a system for a emergency de-' struction of classified materials by burning, using a chlorate candle as the source of oxygen.

There currently exists a great demand for a system f completely, quickly, and efficiently destroy burnable classified materials. These materials are typically paper documents, magnetic and paper tapes, circuit boards, and other types of importantrecords. It is'especially of interest to provide'such a system which may be used in conjunction with the security containers (file cabinets) in which the classified materials are normally stored. Typically, most material is already in the containers and whatever materials are outside may be added quickly with little handling in case of an emergency.

Present methods of destruction involve several problems, such as, personnel safety on activation, lack of efficiency, and ineffectiveness of the oxygen or explosive source from long periods of storage before the system is activated.

One method in present use involves placing an oxidizer (such as sodium nitrate) in slabs or pellets between layers of classified documents. This mixture is then ignited by Thermit. The intimate mixture of fuel with the oxidizer'combined with the high heat of reaction of'the Thermit has occasionally led to explosions. Also, some types of Thermit emit toxic gases when ignited.

Another method involves'the use of explosives directly'. Explosive charges are placed in the security containers along with the classifed material and the charges are set off manually or by unauthorized entry.

SUMMARY OF THE INVENTION The above and other disadvantages of prior art classified material destruction systems are overcome in ac cordance' with the present invention which provides a controlled source of oxygen which may be remote from the material to be destroyed. The system consists of a chlorate candle,- as a source of oxygen, which is stored in each drawer or each container or remotely frornthe container in a furnace. In a destruction sequence, the candle and classified materials are ignited and the oxygen from the candle is delivered to and combined with the materials. The candle design and composition are chosen to provide the proper amount of oxygen and burn rate for the amount of material to be destoryed. A compressed air source may be connected to the system and a blast of compressed air added to the materials at or near the end of the burn to further insure complete combustion of all the material.

It is thus an object of the present'invention to provide for the complete destruction of classified materials by burning.

A second object of the invention is to provide for the safe completedestruction of classified materials without producing toxic gases or explosions.

A third object of the invention is to provide an oxy gen source for the complete-destruction of classified materials which has high efficiency and long storage life withoutdegradation.

A fourth object of the invention is-to provide a system for the complete destruction of classified materials 2 in their storage container so that only a minimum amount of material handling is called for.

A fifth object of the invention is to provide a system for the complete destruction of classified materials with an oxygen source which may be remote from the classifled materials.

Other objects, advantages and novel features of the invention will become apparentfrom the following detailed description of the invention when considered in conjunction with the accompanying drawing.

' BRIEF DESCRIPTION OF THE DRAWING The FIGURE illustrates an embodiment of the invention in schematic form;

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the FIGURE, a one-drawer security container l for classified. material is shown. Classified documents 2 are stored in a conventional (vertical) manner. Steel wool spacers 30f 1 inch thickness are placed between the documents at approximately 4 inch intervals to promote the distribution of oxygen to the documents. A chlorate candle 4 is stored in a submarinetype candle furnace 5. A glass wool filter 6 is placed in output line 9 to remove sodium chloride smoke which is generated with the oxygen by the decomposition of the candle. Valve 15 is a normal on/offvalve.

Igniter 7 is provided in the classified material compartment to initiate combustion of the material. lgniter 8 is connected to candle 4 to initiate the candles combustion. Either or both may be electrical igniters and they may be connected. for simultaneous ignition.

In an emergency situation when classified material must be destroyed, any material outsidecontainer 1 would be placed in it. Tapes and circuit boards may be placed on top of documents 2. The container is secured and both igniters are activated. Candle 4 immediately begins decomposing and releasing oxygen which flows through filter 6 and delivery line 9 to a manifold 10 in the security container. Manifold 10 may consist of a 1 inch diameter pipe with /8 inch diameter holes drilled in it. Oxygen flows through the holes in the manifold through a cast iron grate 11 to the classified materials to support combustion. Exhaust gases from the burn pass through vent l7.

In a test burn, a target load of 7 /2 pounds of paper documents were-completely destroyed in 53 minutes using 112 cubic feet of oxygen (50 percent excess) from a submarine-type chlorate candle. However, a circuit board placed on top of the documents was not adequately destroyed. To aleviate this problem, an optional compressed air source 12 is connected to the container 1 via delivery pipe 13 and nozzle 14. Valve 16 is a normal on/off valve for disconnecting the compressed air source. A compressed air blast of approximately 3 minutes is directed manually or by a timer to the burn at or immediately following the end of the oxygen burn. This raises the temperature to complete destruction of tapes and circuit boards and also combusts any fragments of charred paper and blows the ash out of the container to completely insure full destruction of the classified information.

A regular submarine-type chlorate candle releases approximately 112 cubic feet of oxygen per hour for a well metered burn. By altering the design and composition of the candle, a faster burn of the order of 30 minutes may be achieved. The faster burn would of course be advantageous in an emergency sitution butis still metered to prevent any possible holocaust to occur. The amount of oxygen necessary and the size of the candle to release that amount are easily computed from known chemical data. The chlorate candle is especially well suited for the system as it releases no toxic gases and the technology of producing the candle is well understood. Also, the candle releases 94 percent of its available oxygen and candles have been ignited after being stored for years. Thus, they are reliable, safe, and efficient.

Several alternatives to the separate one-drawer system in the FIGURE are also contemplated. There could be a large separate candle for several containers, or' one candle in each container, or a small candle in each drawer. For example, a separate candle for a fivedrawer security container holding 100 pounds of paper documents should release 83 pounds of oxygen to destroy the documents. An excess factor of forty percent is used to insure a complete burn and to allow for other materials such as tapes and circuts boards to be placed on top of the documents. The requirement then becomes ll6 pounds of oxygen which would require a 350 pound chlorate candle. For a single candle in a five-drawer container, the bottom drawer could hold the candle which would measure inches long by 16 inches wide by 9 inches high. This would be sufficient to burn the 80 pounds of material in the four upper drawers which would be perforated to allow the oxygen to be distributed throughout the container.

Obviously many modifications and. variations of the present invention are possible in light of the above teachings. it is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is: l. A system for destruction of combustable materials comprising:

a container for enclosing said materials; means disposed within said container for igniting said materials; at least one chlorate candle disposed external and proximate to said container; means for enclosing said candle; means for igniting said candle; I

conduit means joining said enclosure means and said container for introducing into said container oxygen generated by said chlorate candle, said conduit means disposed so as to release oxygen below said material. 2. The system for destruction of combustable materials of claim 1 further comprising:

means to introduce a blast of compressed air to said materials timed to occur near the end of the release of oxygen by said candle to thereby further insure complete destruction of said material.

l l l 

1. A system for destruction of combustable materials comprising: a container for enclosing said materials; means disposed within said container for igniting said materials; at least one chlorate candle disposed external and proximate to said container; means for enclosing said candle; means for igniting said candle; conduit means joining said enclosure means and said container for introducing into said container oxygen generated by said chlorate candle, said conduit means disposed so as to release oxygen below said material.
 2. The system for destruction of combustable materials of claim 1 further comprising: means to introduce a blast of compressed air to said materials timed to occur near the end of the release of oxygen by said candle to thereby further insure complete destruction of said material. 